Affordability has a new name. It’s called whitetopping, and cities and counties around the state of Michigan are embracing it as an option to stretch their limited funds even further as they work to maintain their infrastructure.
The Michigan Department of Transportation (MDOT) recently used whitetopping on Gratiot Avenue in Detroit as part of their demonstration projects program. MDOT views whitetopping as a viable option in their “Mix of Fixes” strategy.
“We are continually looking for ways to be more efficient and effective in the selection of project fixes,” said Greg Johnson, region engineer for MDOT. “We feel this demonstration will provide a great opportunity to look at concrete whitetopping in an urban setting.”
The project consisted of rehabilitating a worn-out roadway and replacing it with a smooth surface made of durable concrete. John Carlo Inc. was the contractor for the project. The project involved milling off 5 in. of existing asphalt and laying down a 1-in.-thick asphalt interlayer.
“The 1-in. layer of asphalt was used to separate the old pavement below from the newer concrete pavement above,” stated Brian St. Louis, paving division manager for John Carlo. Four in. of concrete was then placed on the interlayer. The durable new pavement speaks for itself and shows whitetopping has a bright future in Michigan.
“We believe urban whitetopping has a great deal of potential,” Johnson said.
All-around answer
Not only has MDOT embraced this technology, but all around the state cities and counties are looking to stretch their limited funds and find an alternative to the skyrocketing price of asphalt. Whitetopping fits the bill.
Just down the road in Washtenaw County, whitetopping is welcomed as a cost-effective way to rehabilitate roads. Nine years ago, Washtenaw County whitetopped an intersection worn out due to heavy truck traffic. Asphalt fixes were only surviving for about six months. The project involved milling the existing asphalt and placing 4 in. of concrete whitetopping.
“The original intersection was whitetopped because of the severe rutting and shoving of the asphalt that resulted from the heavy truck traffic,” explained Sheryl Siddall, assistant director of engineering for the Washtenaw County Road Commission.
Whitetopping proved to be affordable and durable for Washtenaw County.
“Whitetopping was a cost-effective and appropriate fix for this location,” Siddall added.
Nine years of near-maintenance-free service proves it.
Just like the progressive thinking in MDOT and Washtenaw County, Monroe County has picked up the mantle of whitetopping and used it to its success.
Over the past several years, the flexible pavement on Nadeau Road located just off I-75 in Monroe County had experienced severe rutting. An estimated 400 trucks per day travel Nadeau Road to enter a gas station, restaurant and weigh station. The Monroe County Road Commission had been contemplating a long-term fix for this section of Nadeau Road, and whitetopping seemed a sensible solution. Prior to constructing the whitetopping, core samples of the existing asphalt were taken and revealed between 7 and 12 in. of pavement. The whitetopping was constructed by first milling out 7 in. of the existing asphalt pavement, setting dowel baskets in place and then filling the milled section with concrete. The result is quite impressive.
No longer is there rutting and shoving, and trucks can safely execute turns. This just goes to show that a little innovative thinking can solve ongoing problems with a solid investment in whitetopping. Like the old saying goes, “When trucks hit the road, concrete takes the load.”
Champion of the west, too
Whitetopping is not just a phenomenon that is unique to the east side of the state. It is used in the Kalamazoo and Grand Rapids areas, too.
In Kalamazoo, the asphalt surface at the intersection of Portage Avenue and Cork Street was having a difficult time handling the 23,000 vehicles per day that use it. Instead of replacing the asphalt surface with yet another lift of asphalt pavement, the city decided to utilize whitetopping. The project is the first whitetopping in the southwest region, and Kalamazoo residents can now look forward to years of rut-free service.
The intersection was closed to traffic on Sunday, June 20, and the asphalt surface was milled off. Concrete placement was started on Monday and completed on Thursday morning. Cleanup and traffic marking was completed on Saturday, and the intersection was reopened to traffic in the afternoon. Motorists were inconvenienced a mere six days and now will receive 15-20 years of durable road. This was a first for Kalamazoo, and they are now considering additional projects for whitetopping.
This just goes to show how easy it is and how fast a whitetopping project can be reopened to traffic. In fact, Grand Rapids has had such success with whitetopping that they now use it on a regular basis for their maintenance program.
Kent County initially discovered the value of whitetopping on routes with a high volume of commercial truck traffic.
“Whitetopping is a superior fix for us on heavy commercial routes because the concrete overlay provides a much harder and more durable surface than asphalt,” Wayne Harrall, director of engineering for the Kent County Road Commission, explained.
Patterson Avenue was a prime candidate for whitetopping, and Kent County jumped at the chance to employ a cost-effective and long-lasting fix. The road services several businesses and manufacturing facilities in the area. It was in poor condition and had been scheduled for repair in 2006. The road was initially constructed of 103?4 in. of hot-mix asphalt.
Over the years, the asphalt had become seriously rutted and was breaking apart under the stress of the daily pounding of heavy trucks. The road commission considered several alternatives and decided whitetopping would give them the harder, more durable surface necessary to withstand heavier loads.
“We have seen good results with the whitetopping and find it to be more durable than hot-mix asphalt,” Harrall said.
The project required milling down 4 in. of asphalt and replacing it with 4 in. of concrete. Five 12-ft lanes between 44th Street and 36th Street were resurfaced, and the intersection on the north end of the project at 36th Street was reconstructed.
The end result is a road that is durable and cost effective and will provide motorists with a smooth ride for many years to come.
Always has an answer
Despite the numerous successes of whitetopping, skeptics still exist. Some say they cannot afford concrete. With the recent spike in oil prices and, ultimately, asphalt, concrete is not only cost effective in the long run but often more affordable in first-cost; the cost differential between petroleum-based asphalt and concrete has shrunk. Cities and counties around the state have learned that, considering all the options, either concrete or asphalt is the best way to stretch your limited funds. Whitetopping is one more tool in the tool box that maximizes performance and durability while stretching finances.
Some skeptics ask, What do you do at the end of whitetopping’s service life?
The answer is you can “mill-and-fill” whitetopping like a traditional asphalt overlay. Whitetopping can be milled and filled as easily as asphalt. In fact, it has been done in Michigan.
Washtenaw County proved the versatility of whitetopping when they replaced their original whitetopping with a complete reconstruction of a heavily traveled intersection.
“We would have preferred to take the whitetopping further but we couldn’t turn away the funding,” said Mike Bernbeck, construction supervisor for the Washtenaw County Road Commission.
A milling machine successfully milled the 4-in. whitetopping with the standard asphalt milling equipment and confirmed the feasibility of a concrete mill-and-fill. The milling machine cut through the whitetopping at different depths—2 in., 4 in. and 5 in. It easily passed through the different depths without damaging the underlying pavement.
“The different depths were to show it could be milled and examine how the pavement performed,” explained Bernbeck.
Whether you’re MDOT, Monroe County, the city of Kalamazoo or even Washtenaw County, whitetopping has proven itself to be the right fix. Whitetopping is easy to install, cost effective, can be opened to traffic in a very short time and is recyclable.
